Mustique is about as safe and clean as you can expect for a tourist destination. The island is privately owned and there are very few locals, so petty theft is rare and violent crimes are virtually non-existent. That being said, Mustique is still an island that attracts some very wealthy visitors, so it is still a good idea to be cautious. Lock valuables up securely and do not carry too much money on your person when you are out and about. Otherwise, Mustique is very safe even in the evenings.

The more likely dangers come from the environment. Remember that Mustique is in the tropics and days here are usually sunny. Make sure to protect yourself from sunstroke and sunburn.

Another thing to watch out for on Mustique is the Machineel tree, which is commonly found on beaches around the island. The fruit is toxic and the sap causes skin irritation, so steer clear of them and keep children away as well.

It may also be a good idea to get a Hepatitis A vaccination a month or more before leaving for the island, as there is some risk of infection on all Caribbean islands. A Hepatitis B shot may also be advisable if you plan to stay 6 months or more in Mustique.